Educational inequalities in blood pressure across the adult life course: Evidence from a 20-year follow-up study

Aim: High blood pressure (BP) is a key contributor to the burden of disease. This study aimed to assess: a) educational differences across the entire BP distribution, and b) educational differences in the trajectories of BP across the adult life course.Method: Longitudinal data from the Stockholm Diabetes Prevention Program was analysed using quantile regression and linear mixed effects models. Models were adjusted for age, sex, lifestyle, and BP medication.Results: Lower educational level was associated with higher systolic BP (SBP) at all follow-up periods. Age and sex adjusted mean SBP was 2.49 (95% confidence interval (CI) 1.10, 3.87), 3.95 (95% CI 2.45, 5.45) and 2.61 (95% CI 1.09, 4.13) mmHg higher for people with pre-secondary education compared with post-secondary at baseline, 10 years and 20 years follow-up, respectively. Quantile regressions revealed that the inequalities could be observed across the entire BP continuum. Longitudinally analysed, people with pre-secondary education had 3.01 (95% CI 1.91-4.11) mmHg higher SBP than those with post-secondary education, age and sex adjusted. No significant convergence or divergence of the educational gaps in SBP was observed. Educational differences remained even after adjusting for lifestyle and BP medication.Conclusions: These results imply that public health interventions should aim to bring about distributional shifts in blood pressure, rather than exclusively focusing on hypertensive people, if they are to effectively minimize the educational disparities in blood pressure and its consequences.